Visual gamma oscillations in schizophrenia: Implications for understanding neural circuitry abnormalities

Gamma oscillations may play an important role in the representation of information in the brain by synchronizing the firing of neurons in local and distributed neural circuits. The Bleulerian conceptualization of schizophrenia as disintegration of thought and personality suggests that neural mechanisms responsible for the integration of neural activity, such as gamma oscillations, might be particularly disrupted in this disorder. Here we review studies of gamma oscillations in healthy and schizophrenic individuals performing visual perception tasks. The findings suggest that schizophrenia is associated with a variety of abnormalities of visual gamma oscillations, which appear to be linked to core symptoms and cognitive deficits of schizophrenia. The relationships between these abnormalities and neural circuitry abnormalities in schizophrenia are discussed.